When a host fish dies, C. exigua will detach itself from the tongue stub after some time, leave the fish's mouth cavity, and can then be seen clinging to its head or body externally.
Reproduction
It exhibits sexual reproduction. It is likely that juveniles first attach to the gills of a fish and become males. As they mature, they become females, with mating likely occurring on the gills. If there is no female present, within a pair of two males, one male can turn into a female after it grows to 10 millimetres (0.4 in) in length. The female then makes its way to the fish's mouth where it uses its front claws to attach to the fish's tongue.